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As the novel opens, readers learn that the boys' plane has crashed on an uninhabited island. As the children begin to gather on the beach to try to figure out what happened (and what they should do next), Piggy suggests that Ralph blow the conch as a signal for everyone to come together for a meeting. Eventually, the boys learn to associate the sound of the conch with a summons, and understand that they must come to order when the shell is blown. Thus, the conch shell comes to symbolize order in the novel, and whoever has the conch has the right to speak.

As chaos begins to take over on the island, the conch becomes less effective; the boys start to ignore its sound, and Ralph becomes frustrated when he realizes that he's losing control. Ultimately, in the altercation that results in Piggy's death, the conch is shattered; this act symbolizes the complete loss of order on the island.

Again, you've asked a very complex question--one that requires an answer that is too in-depth to be posted here. I hope this helps you get started. Good luck!

In Lord of the Flies, Golding uses the people and objects as symbols of something bigger. The conch is one of those symbols. Piggy, symbolic of intellect and intelligence, is the first to spot the conch. Once Ralph gets it and figures out how to blow it (with Piggy's help), it becomes the symbol of organization and civilization. When the boys hear it they gather, and whoever holds it has the power and privilege to speak and be heard. It works for a while.

Like all shells, the conch grows thin and faded over time by the sand and the sun. Symbolically, it's losing its impact as its physical presence is diminishing. At one point, Ralph is even afraid to blow the conch because he's afraid no one will come--and they will no longer be civilized. Finally, Piggy has had his glasses stolen by Jack and his "savages" and wants to confront them. He clings blindly to the fragile conch and climbs the mountain. He (and his request for a more civilized way of acting) is mocked and scorned. Some of the savages lever a rock on him and kill him, smashing the conch in the process. It is the last vestige of civilization on the island, and what happens next is a hunt to the death--until they are rescued. The conch, then, is a symbol of all things civilized, and as the conch goes, so goes the behavior of the boys.